(1) Field of the Invention
The present invention relates to a process for preparing a 1-benzylimidazole compound by benzylation of a 1-unsubstituted imidazole, and also to a novel 1-benzylimidazole compound. The 1-benzylimidazole compound is valuable as a curing agent and a curing promoter for a polyepoxy resin.
(2) Description of the Related Art
A process for reacting a 1-unsubstituted imidazole compound with benzyl chloride, cooperating with an HC acceptor in an appropriate solvent having no active hydrogen atom is known [see, for example, Recl. Trev. Chim. Pays-Bas, Vol. 91, No. 12, 1383-1392 (1972)].
This benzylation process, however, involves the following problems. Namely, the 1-imidazole compound formed by the reaction between the 1-unsubstituted imidazole compound and benzyl chloride is likely to react further with unreacted benzyl chloride to form a 1,3-dibenzyl imidazolium chloride compound, and therefore, the unnecessary imidazolium chloride is formed as a by-product in a large quantity. Moreover, benzyl chloride is difficult to handle because of the lacrimatory property.